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Test ID PTNT Prothrombin G20210A Mutation, Blood

Ordering Guidance

This assay will only detect the F2 c.*97G>A (rs1799963) variant associated with thrombophilia. To detect other pathogenic alterations in the F2 gene of a patient with a laboratory diagnosis of thrombophilia, order F2NGS / F2 Gene Next Generation Sequencing, Varies.


This assay will not detect alterations in individuals with thrombophilia caused by mechanisms other than the F2 c.*97G>A variant. For those situations consider ordering AATHR / Thrombophilia Profile, Plasma and Whole Blood.

Specimen Required

Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.


Preferred: Lavender top (EDTA)

Acceptable: Yellow top (ACD solution B), light-blue top (sodium citrate)

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube. Do not aliquot.


1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. Coagulation Patient Information (T675) in Special Instructions 

Useful For

Patients with clinically suspected thrombophilia


Determination of the duration of anticoagulation therapy of venous thromboembolism patients


Screening for women contemplating hormone therapy

Method Name

Direct Variant Analysis

Reporting Name

Prothrombin G20210A Mutation, B

Specimen Type

Whole blood

Specimen Minimum Volume

1 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole blood Ambient (preferred) 14 days
  Frozen  14 days
  Refrigerated  14 days

Reference Values


Day(s) Performed


Report Available

3 to 5 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

81240-F2 (prothrombin, coagulation factor II) (eg, hereditary hypercoagulability) gene analysis, 20210G>A variant

LOINC Code Information

Test ID Test Order Name Order LOINC Value
PTNT Prothrombin G20210A Mutation, B 24475-6


Result ID Test Result Name Result LOINC Value
21803 Prothrombin G20210A Mutation, B 24475-6
21804 PTNT Interpretation 69049-5
21806 PTNT Reviewed By 18771-6